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| author | Gregory CLEMENT <gregory.clement@free-electrons.com> | 2012-10-12 19:20:36 +0200 |
|---|---|---|
| committer | Gregory CLEMENT <gregory.clement@free-electrons.com> | 2012-11-21 17:07:49 +0100 |
| commit | e60304f8cb7bb545e79fe62d9b9762460c254ec2 (patch) | |
| tree | 9f28a557c71cf6128c7cf480b8a4a59f0c0bb6b8 /Documentation | |
| parent | arm: plat-orion: Add coherency attribute when setup mbus target (diff) | |
| download | linux-e60304f8cb7bb545e79fe62d9b9762460c254ec2.tar.xz linux-e60304f8cb7bb545e79fe62d9b9762460c254ec2.zip | |
arm: mvebu: Add hardware I/O Coherency support
Armada 370 and XP come with an unit called coherency fabric. This unit
allows to use the Armada 370/XP as a nearly coherent architecture. The
coherency mechanism uses snoop filters to ensure the coherency between
caches, DRAM and devices. This mechanism needs a synchronization
barrier which guarantees that all the memory writes initiated by the
devices have reached their target and do not reside in intermediate
write buffers. That's why the architecture is not totally coherent and
we need to provide our own functions for some DMA operations.
Beside the use of the coherency fabric, the device units will have to
set the attribute flag of the decoding address window to select the
accurate coherency process for the memory transaction. This is done
each device driver programs the DRAM address windows. The value of the
attribute set by the driver is retrieved through the
orion_addr_map_cfg struct filled during the early initialization of
the platform.
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Reviewed-by: Yehuda Yitschak <yehuday@marvell.com>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/devicetree/bindings/arm/coherency-fabric.txt | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/Documentation/devicetree/bindings/arm/coherency-fabric.txt b/Documentation/devicetree/bindings/arm/coherency-fabric.txt index 2bfbf67dd77e..17d8cd107559 100644 --- a/Documentation/devicetree/bindings/arm/coherency-fabric.txt +++ b/Documentation/devicetree/bindings/arm/coherency-fabric.txt @@ -5,12 +5,17 @@ Available on Marvell SOCs: Armada 370 and Armada XP Required properties: - compatible: "marvell,coherency-fabric" -- reg: Should contain,coherency fabric registers location and length. + +- reg: Should contain coherency fabric registers location and + length. First pair for the coherency fabric registers, second pair + for the per-CPU fabric registers registers. Example: coherency-fabric@d0020200 { compatible = "marvell,coherency-fabric"; - reg = <0xd0020200 0xb0>; + reg = <0xd0020200 0xb0>, + <0xd0021810 0x1c>; + }; |